Until today I used a Sandisk ExtremeIII SD card with 2.0 GB to run zubuntu via kexecboot kernel which worked like a chrm.

Today I formatted a 4GB Transcend card with ext3 and installed zubuntu on it. The result is somehow demotivating- themultiboot kernel starts, probes mmcblk0p1 and then returns with "no bootable device found". The boot flag is set on the partition.

I tried several things to solve the issue- shrink the partition to 1 GB, copied the root filesystem from the 2GB card- same result.

Interesting: Starting with the 2GB card until the multiboot display appears and then exchanging the SD cards works. So it is not the card itself, propably.